Charged particle beam apparatus

ABSTRACT

This charged particle beam apparatus is provided with: a charged particle beam lens-barrel for irradiating a sample with a charged particle beams; a tilting base that has a first sample holding portion capable of holding the sample and that holds the first sample holding portion to be turnable about a first axis; a tilting base that has a second sample holding portion capable of holding the sample and that holds the second sample holding portion to be turnable about a second axis parallel to the first axis; and a driving force supplier that supplies to the tilting bases with a driving force for turning the tilting bases in association with each other.

RELATED APPLICATIONS

This application is a 371 application of PCT/JP2018/012609 having aninternational filing date of Mar. 27, 2018, with claims priority toJP2017-060903 filed Mar. 27, 2017 and JP2018-055231 filed Mar. 22, 2018,the entire content of which is incorporated herein by reference.

TECHNICAL FIELD

The present invention relates to a charged particle beam apparatus.

BACKGROUND ART

The charged particle beam is a generic term for the ion beam and theelectron beam. An apparatus capable of performing at least one ofprocessing, observation and analysis (hereinafter referred toobservation or the like) using a focused charged particle beam is calleda charged particle beam apparatus. The charged particle beam apparatusis mounted with at least one of an ion beam lens barrel forming the ionbeam and an electron beam lens barrel forming the electron beam. Thecharged particle beam apparatus also includes a combined device on whicha plurality of charged particle beam lens barrels are mounted.

Such a charged particle beam apparatus may be used, for example, to forma thin sample. When a structure such as a semiconductor device isexposed on an observation surface of the thin sample, a processing rateof the charged particle beam varies depending on the presence or absenceof the structure. Thus, an unevenness is formed on the observationsurface and a phenomenon of streaky appearance, so-called curtain effectoccurs.

For example, Patent Literature 1 describes a composite charged particlebeam apparatus capable of tilting a sample base on which a sample isplaced in a biaxial direction in order to prevent the curtain effect.

CITATION LIST Patent Literature

Patent Literature 1: JP-A-2014-063726

SUMMARY OF INVENTION

Technical Problem

However, when a plurality of samples are disposed in a sample holder toprocess the samples in order to form a sample efficiently, the chargedparticle beam apparatus in the related art has the following problem.

In the composite charged particle beam apparatus described in PatentLiterature 1, the sample holder is disposed such that the tilting axispasses through one sample on the sample holder. When a plurality ofsamples are disposed in the sample holder, the sample disposed outsidethe tilting axis moves about the tilting axis when the sample holder istilted. Thus, there is a problem of repositioning each sample to a beamirradiation position. In addition, when the sample holder is tilted,there is a concern that the sample disposed outside the tilting axiscollides with a structure such as a lens barrel to damage the sample.

The present invention has been made in view of the above problem, and anobject of the present invention is to provide a charged particle beamapparatus capable of safely and efficiently forming a sample even in acase of processing a plurality of samples.

Solution to Solve Problem

In order to solve the above problem, a charged particle beam apparatusaccording to a first aspect of the present invention includes:

a charged particle beam lens barrel that irradiates a sample with acharged particle beam;

a first tilting base that includes a first sample holding portioncapable of holding the sample, and holds the first sample holdingportion to be turnable about a first turning axis;

a second tilting base that includes a second sample holding portioncapable of holding the sample, and holds the second sample holdingportion to be turnable about a second turning axis parallel to the firstturning axis; and

a driving force supplier configured to supply the first tilting base andthe second tilting base with a driving force for turning the firsttilting base in association with the second tilting base.

In the present description, “turn” means a revolving movement about aturning axis, limited by an angular range of less than 360°. Thedirection of “turn” can be two directions about the turning axis.

In the above charged particle beam apparatus, the first tilting base andthe second tilting base may be disposed in a direction intersecting thefirst turning axis and the second turning axis.

The above charged particle beam apparatus may further include a samplestage that includes a rotation stage being rotatable about a rotationaxis extending in a direction orthogonal to the first turning axis andthe second turning axis, in which the first tilting base and the secondtilting base may be provided on a detachable sample holder on an uppersurface of the sample stage.

In the present description, “rotation” means a revolving movement abouta rotation axis. That is, “rotation” means includes the meaning of botha revolving movement about the rotation axis within an angular range ofless than 360° and a revolving movement about the rotation axis at anangle of 360° or more. The angle of “rotation” may or may not belimited. The direction of “rotation” may be two directions about therotation axis or may be limited to one direction.

The above charged particle beam apparatus may further includes a tiltingstage that turns the first tilting base and the second tilting baseabout a third turning axis orthogonal to the first turning axis and thesecond turning axis.

In the above charged particle beam apparatus, the first tilting base mayinclude a first gear having the first turning axis as a pitch circlecenter, the second tilting base may include a second gear having thesecond turning axis as a pitch circle center, and the driving forcesupplier may include a third gear meshing with the first gear and thesecond gear.

In the above charged particle beam apparatus, the first gear may be afirst worm wheel, the second gear may be a second worm wheel, and thethird gear may be a worm meshing with the first worm wheel and thesecond worm wheel.

In the charged particle beam apparatus, the driving force supplier mayinclude a drive rod that transmits the driving force to the firsttilting base and the second tilting base.

Advantageous Effects of Invention

According to the charged particle beam apparatus of the presentinvention, a sample can be safely and efficiently formed even in a caseof processing a plurality of samples.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic diagram showing an example of a configuration of acharged particle beam apparatus according to a first embodiment of thepresent invention.

FIG. 2 is a schematic perspective view showing a configuration of mainparts of the charged particle beam apparatus according to the firstembodiment of the present invention.

FIG. 3 is a schematic perspective view showing a main configuration of asample holder in the charged particle beam apparatus according to thefirst embodiment of the present invention.

FIG. 4 is a detailed diagram of a portion A in FIG. 3.

FIG. 5 is a schematic front view showing an example of an internalstructure of the sample holder in the charged particle beam apparatusaccording to the first embodiment of the present invention.

FIG. 6 is an operation illustrative diagram of the sample holder in thecharged particle beam apparatus according to the first embodiment of thepresent invention.

FIGS. 7A and 7B show a schematic front view and side view showing theholding form of the sample in the charged particle beam apparatusaccording to the first embodiment of the present invention.

FIG. 8 is a schematic perspective view showing a relationship betweenthe sample and a processing direction in the charged particle beamapparatus according to the first embodiment of the present invention.

FIG. 9 is a schematic front view showing an example of an internalstructure of a sample holder in a charged particle beam apparatusaccording to a second embodiment of the present invention.

FIG. 10 is a schematic front view showing an example of an internalstructure of a sample holder in a charged particle beam apparatusaccording to a third embodiment of the present invention.

FIG. 11 is a schematic front view showing an example of an internalstructure of a sample holder in a charged particle beam apparatusaccording to a fourth embodiment of the present invention.

FIG. 12 is a schematic front view showing an example of an internalstructure of a sample holder in a charged particle beam apparatusaccording to a modification of the fourth embodiment of the presentinvention.

FIG. 13 is a schematic front view showing an example of an internalstructure of a sample holder in a charged particle beam apparatusaccording to a fifth embodiment of the present invention.

FIG. 14 is a schematic front view showing an example of an internalstructure of a sample holder in a charged particle beam apparatusaccording to a modification of the fifth embodiment of the presentinvention.

DESCRIPTION OF EMBODIMENTS

Hereinafter, embodiments of the present invention will be described withreference to the attached drawings. In all the drawings, the same orcorresponding members are denoted by the same reference numerals even ifthe embodiment is different, and the common description is omitted.

First Embodiment

A charged particle beam apparatus according to a first embodiment of thepresent invention will be described.

FIG. 1 is a schematic diagram showing an example of a configuration of acharged particle beam apparatus according to the first embodiment of thepresent invention. FIG. 2 is a schematic perspective view showing aconfiguration of main parts of the charged particle beam apparatusaccording to the first embodiment of the present invention. Since eachdrawing is a schematic view, the shape and dimensions are exaggerated(the same applies to the following drawings).

As shown in FIG. 1, a charged particle beam apparatus 100 of the presentembodiment includes a sample chamber 9, a sample stage 10, an FIB lensbarrel 1 (charged particle beam lens barrel), an EB lens barrel 2(charged particle beam lens barrel), a GIB lens barrel 3 (chargedparticle beam lens barrel), a gas gun 19, and a sample holder 6.

Here, “FIB” is an abbreviation standing for Focused Ion Beam, “EB” is anabbreviation standing for Electron Beam. “GIB” is an abbreviationstanding for Gas Ion Beam.

The sample chamber 9 accommodates therein samples 7A and 7B to beprocessed, observed, and/or analyzed by the charged particle beamapparatus 100. The samples 7A and 7B are minute thin pieces. In FIG. 1,the size of the samples 7A and 7B is greatly exaggerated for easyviewing. The sample chamber 9 is connected to a vacuum exhaust apparatus(not shown) for changing and maintaining a degree of vacuum inside thesample chamber 9.

The sample chamber 9 may be provided with a load lock chamber (notshown) such that the sample can be carried in and out without changingthe internal atmosphere and the vacuum state.

The sample stage 10 is built in the sample chamber 9. In the samplechamber 9, the FIB lens barrel 1, the EB lens barrel 2, and the GIB lensbarrel 3 are disposed at positions facing the sample stage 10.

The sample stage 10 is configured to include a rotation stage 5. In thepresent embodiment, the sample stage 10 includes a 5-axis moving stage.

The rotation stage 5 is disposed on the top of the sample stage 10.Below the rotation stage 5, an XYZ stage (not shown) and a tilting stage(not shown) are disposed.

As shown in FIG. 2, a tilting stage includes a tilting drive unit 8 fortilting the sample stage 10 by turning the rotation stage 5 about anaxis 8 a in a horizontal plane.

The rotation stage 5 includes a sample base 5 a and a rotation driveunit 5 b. The sample base 5 a is configured to be able to detach orattach a sample holder 6 to be described later. The rotation drive unit5 b rotates the sample base 5 a about a rotation axis C. When thetilting stage (not shown) in the sample stage 10 is at a referenceposition of tilt, the rotation axis C is parallel to a vertical axis.

An upper surface of the sample base 5 a is provided with anattachment/detachment mechanism (not shown) for positioning andattaching/detaching the sample holder 6 to be described later.

The rotation drive unit 5 b includes, for example, a rotation supportportion (not shown) for rotatably holding the sample base 5 a, a motor(not shown) for supplying a driving force for rotating the sample base 5a, and a transmission mechanism for transmitting the driving force ofthe motor to the sample base 5 a.

As shown in FIG. 2, the FIB lens barrel 1 is disposed above the samplestage 10 to face the sample stage 10. In the present embodiment, as anexample, the FIB lens barrel 1 is disposed parallel to the verticalaxis.

The FIB lens barrel 1 emits an FIB 1 b as a first charged particle beamalong an FIB irradiation axis 1 a parallel to the vertical axis. The FIBlens barrel 1 includes, for example, a liquid metal ion source.

The EB lens barrel 2 is disposed above the sample stage 10 along an axistilted with respect to the vertical axis. The EB lens barrel 2 emits anEB 2 b as a second charged particle beam along an EB irradiation axis 2a tilted with respect to the vertical axis.

The GIB lens barrel 3 is disposed above the sample stage 10 along anaxis tilted in a direction different from that of the EB lens barrel 2with respect to the vertical axis. The GIB lens barrel 3 emits a GIB 3 bas a third charged particle beam along a GIB irradiation axis 3 a tiltedin a direction different from that of the EB lens barrel 2 with respectto the vertical axis.

The GIB lens barrel 3 includes, for example, a PIG gas ion source.Examples of the gas ion source include helium, argon, xenon, or oxygenas an ion source gas.

The FIB irradiation axis 1 a intersects the GIB irradiation axis 3 a ata predetermined position above the sample stage 10 on a plane Pincluding the axis 8 a and the vertical axis. The EB irradiation axis 2a intersects the FIB irradiation axis 1 a and the GIB irradiation axis 3a at the predetermined position where the FIB irradiation axis 1 aintersects the GIB irradiation axis 3 a, that is, the FIB 1 b, the EB 2b, and the GIB 3 b intersect one another at the predetermined position.

The charged particle beam apparatus 100 further includes a secondaryelectron detector 4 for detecting secondary electrons generated from thesample 7A (7B) by irradiation with the EB 2 b, the FIB 1 b, or the GIB 3b. Further, the charged particle beam apparatus 100 may include abackscattered electron detector for detecting backscattered electronsgenerated from the sample by irradiation with the EB 2 b.

As shown in FIG. 1, the gas gun 19 supplies an etching gas nearirradiation regions of the FIB 1 b, the EB 2 b, and the GIB 3 b.Examples of the etching gas include halogen gases such as a chlorinegas, a fluorine-based gas (such as xenon fluoride and fluorine carbide),and an iodine gas. When the gas gun 19 supplies an etching gas reactingwith the material of the sample 7A (7B) to the irradiation region of theFIB 1 b, the EB 2 b, or the GIB 3 b, the sample 7A (7B) is subjected togas-assisted etching by the FIB 1 b, the EB 2 b, or the GIB 3 b.Particularly in the gas-assisted etching by the EB 2 b, etching can beperformed without damaging the sample 7A (7B) by ion sputtering.

The sample holder 6 includes two tilting bases which turn the samples 7Aand 7B about a first turning axis and a second turning axisrespectively, and a tilting stage which turns the two tilting basesabout a third turning axis orthogonal to the first turning axis and thesecond turning axis. A specific configuration example of the sampleholder 6 will be described later.

Next, a configuration of a control system of the charged particle beamapparatus 100 will be described.

As shown in FIG. 1, the charged particle beam apparatus 100 includes asample stage control unit 15, a sample holder control unit 40, an FIBcontrol unit 11, an EB control unit 12, a GIB control unit 13, an imageforming unit 14, and a control unit 17.

The sample stage control unit 15 is communicably connected to each stagedrive unit of the sample stage 10. The stage drive unit includes therotation drive unit 5 b and the tilting drive unit 8.

The sample stage control unit 15 moves each stage of the sample stage 10by controlling each stage drive unit based on a control signal from thecontrol unit 17 to be described later. For example, under the control ofthe sample stage control unit 15, the rotation drive unit 5 b drives thesample base 5 a to rotate. For example, under the control of the samplestage control unit 15, the tilting drive unit 8 drives a tilting stage(not shown) to tilt.

The sample holder control unit 40 is communicably connected to a driveunit in the sample holder 6 via a wiring (not shown) when the sampleholder 6 to be described later is disposed on the sample base 5 a.

The sample holder control unit 40, in a state of being connected to thesample holder 6, tilts the tilting base and the tilting stage of thesample holder 6 based on a control signal from the control unit 17 to bedescribed later. Accordingly, the sample holder control unit 40 canchange the tilting of the samples 7A and 7B held on the sample holder 6with respect to the rotation axis C in a biaxial direction.

The FIB control unit 11 controls FIB irradiation from the FIB lensbarrel 1 based on a control signal from the control unit 17 to bedescribed later.

The EB control unit 12 controls EB irradiation from the EB lens barrel 2based on a control signal from the control unit 17 to be describedlater.

The GIB control unit 13 controls GIB irradiation from the GIB lensbarrel 3 based on a control signal from the control unit 17 to bedescribed later.

The image forming unit 14, for example, forms an SEM image based on asignal obtained by the EB control unit 12 controlling the EB to performscanning and a secondary electron signal detected by the secondaryelectron detector 4. Further, the image forming unit 14 forms a scanningion microscope (SIM) image based on a signal obtained by the FIB controlunit 11 controlling the FIB to perform scanning and a secondary electronsignal detected by the secondary electron detector 4.

The SEM image and the SIM image formed by the image forming unit 14 aresent to the control unit 17 to be described later.

The control unit 17 is communicably connected to the sample stagecontrol unit 15, the sample holder control unit 40, the FIB control unit11, the EB control unit 12, the GIB control unit 13, the image formingunit 14, an input unit 16, and a display unit 18.

The input unit 16 is a device for performing an operation input by anoperator of the charged particle beam apparatus 100. The operation inputwhich is input to the input unit 16 is sent to the control unit 17.

The display unit 18 is a device for displaying information sent from thecontrol unit 17.

The control unit 17 analyzes the operation input sent from the inputunit 16 and generates a control signal for overall control over thecharged particle beam apparatus 100. The control unit 17 sends, asnecessary, the generated control signal to the sample stage control unit15, the sample holder control unit 40, the FIB control unit 11, the EBcontrol unit 12, the GIB control unit 13, and the image forming unit 14.

The control unit 17 sends information on observation images such as anSEM image and an SIM image sent from the image forming unit 14 andinformation on various control conditions of the charged particle beamapparatus 100 to the display unit 18, and displays the above informationon the display unit 18.

Specific control performed by the control unit 17 will be describedlater together with the operation of the charged particle beam apparatus100.

The configuration of the control system including the sample stagecontrol unit 15, the sample holder control unit 40, the FIB control unit11, the EB control unit 12, the GIB control unit 13, the image formingunit 14, and the control unit 17 described above may be configured byappropriate hardware and a computer including a CPU, a memory, aninput/output interface, an external storage device, and the like. A partor all of each control function of the control system may be implementedby a computer executing a control program for implementing each controlfunction.

Next, a detailed configuration of the sample holder 6 will be described.

FIG. 3 is a schematic perspective view showing a main configuration ofthe sample holder in the charged particle beam apparatus according tothe first embodiment of the present invention. FIG. 4 is a detaileddiagram of a portion A in FIG. 3. FIG. 5 is a schematic front viewshowing an example of an internal structure of the sample holder in thecharged particle beam apparatus according to the first embodiment of thepresent invention. FIG. 6 is an operation illustrative diagram of thesample holder in the charged particle beam apparatus according to thefirst embodiment of the present invention.

As shown in FIG. 3, the sample holder 6 includes a base 61, supportportions 62, a turning base 63, a tilting base 64A (first tilting base),a tilting base 64B (second tilting base), and a drive unit 66. However,only the main configuration is schematically drawn in FIG. 3 for easyviewing.

Hereinafter, in a case of describing the configuration of the sampleholder 6, an xy coordinate system may be referred to corresponding tothe disposing posture of the sample holder 6 on the sample based 5 a.

The x-axis and y-axis in the xy coordinate system are orthogonal to eachother. The x-axis and y-axis are fixed on the upper surface of thesample base 5 a.

The base 61 can be placed on the upper surface of the sample base 5 a,and has an outer shape capable of being positioned in the biaxialdirection within the upper surface of the sample base 5 a by apositioning mechanism (not shown). In the example shown in FIG. 3, thebase 61 has a rectangular plate-like outer shape which is long in thex-axis direction. For example, side surfaces of the base 61 in thex-axis direction and the y-axis direction may be used as a positioningunit with the positioning mechanism.

A recess 61 a having a substantially rectangular shape in a plan view isformed in an upper surface of the base 61.

The support portions 62 are provided upright at both ends in the x-axisdirection in the recess 61 a. Each support portion 62 is provided with asupport shaft 62 a extending coaxially with an axis F (third turningaxis) parallel to the x-axis.

In the recess 61 a, a turning base 63 (tilting stage) having arectangular shape in a plan view is disposed between the supportportions 62. At both end portions of the turning base 63 in the x-axisdirection, bearing portions 63 b rotatably connected to the supportshafts 62 a of the support portions 62 are provided above the turningbase 63, respectively. Accordingly, the turning base 63 is supported tobe turnable about the axis F.

The turning base 63 is connected to a turning base drive unit (notshown) via a transmission mechanism (not shown). The turning base driveunit is communicably connected to the sample holder control unit 40. Theturning base drive unit turns the turning base 63 about the axis F basedon a control signal from the sample holder control unit 40. When theturning base 63 is turned about the axis F, the turning base 63 istilted in the y-axis direction.

A hole portion 63 a opening upward is formed in a center portion of theturning base 63 in a plan view. The tilting bases 64A and 64B areaccommodated in the hole portion 63 a side by side in the x-axisdirection. Positions of the tilting bases 64A and 64B in the y-axisdirection are positioned by a positioning unit (not shown) on an innerperipheral portion of the hole portion 63 a.

The tilting bases 64A and 64B may have different shapes, but in thepresent embodiment, they have the same shape.

FIG. 4 shows an example of a detailed configuration of the tilting base64A. Hereinafter, the structure of the tilting base 64A common to thetilting base 64B will be described.

As shown in FIG. 4, the tilting base 64A has a substantially half-moonshape when viewed from the y-axis direction. A worm wheel 64 a isprovided on an arc-shaped outer peripheral portion of the tilting base64A.

A guide groove 64 e concentrically curved with a pitch circle of theworm wheel 64 a is formed on a side surface of the tilting base 64A inthe y-axis direction.

A sample holding portion 64 c for holding the sample 7A via a TEM grid67 is disposed on a plane portion 64 b of the tilting base 64A facingthe worm wheel 64 a.

Similarly, a sample holding portion 64 c for holding the sample 7B via aTEM grid 67 is disposed on the plane portion 64 b of the tilting base64B facing the worn wheel 64 a.

The sample holding portion 64 c disposed on the tilting base 64Aconstitutes a first sample holding portion. The sample holding portion64 c disposed on the tilting base 64B constitutes a second sampleholding portion.

Inside the turning base 63, a worm 70 (a third gear, a driving forcesupplier) is disposed below the tilting base 64A.

As shown in FIG. 5, the worm 70 extends parallel to the x-axis, andmeshes with the worn wheels 64 a of the tilting bases 64A and 64B frombelow.

Both ends of the worm 70 in the axial direction are supported by bearingbases 63 d and 63 e inside the turning base 63 via bearings 71,respectively. The worm 70 is rotatably supported by each bearing 71.

An inter-axis distance between the worm 70 and each worm wheel 64 a isregulated by each roller 65 in contact with each guide groove 64 e in arollable manner. As shown in FIG. 4, the roller 65 in contact with theguide groove 64 e of the tilting base 64A is rotatably supported by thesupport shaft 65 a extending in the y-axis positive direction from thesupport portion 63 c on the upper surface of the turning base 63. Thus,the roller 65 in contact with the guide groove 64 e of the tilting base64A is rotatable about an axis G1 parallel to the y-axis.

As shown in FIG. 5, similar to the roller 65 in contact with the guidegroove 64 e of the tilting base 64A, the roller 65 in contact with theguide groove 64 e of the tilting base 64B is also rotatably supported bythe turning base 63 (not shown) and the support shaft 65 a (not shown).However, the roller 65 in contact with the guide groove 64 e of thetilting base 64B is rotatable about an axis G2 parallel to the axis G1.

With such a configuration, when the worm 70 is driven to rotate, thetilting bases 64A and 64B turn in a state where the inter-axis distancebetween the worm 70 and each worm wheel 64 a is maintained by eachroller 65. As shown in FIG. 6, as a result, the tilting bases 64A and64B turn about an axis S1 (first turning axis) and an axis S2 (secondturning axis) parallel to the y-axis through a pitch circle center ofeach worm wheel 64 a. The worm wheel 64 a of the tilting base 64A is afirst worm wheel and constitutes a first gear having the axis S1 whichis the first turning axis as the pitch circle center. The worm wheel 64a of the tilting base 64B is a second worm wheel and constitutes asecond gear having the axis S2 which is the second turning axis as thepitch circle center.

Accordingly, the plane portions 64 b of the tilting bases 64A and 64Bare tilted in the x-axis direction together with the rotation of theworm 70. When the rotation direction of the worm 70 is switched, thetilting bases 64A and 64B tilt in the opposite direction.

In the present embodiment, since the tilting bases 64A and 64B have thesame shape, tilting directions, tilting speeds, and tilting angles ofthe tilting bases 64A and 64B are the same.

The drive unit 66 has a drive source for supplying a driving force tothe sample holder 6. The drive unit 66 may be disposed at a position onthe sample holder 6, but in the present embodiment, as shown in FIG. 3,the drive unit 66 is attached to one end of the base 61 in the x-axisdirection.

The drive unit 66 in the present embodiment includes two drive sourcesfor supplying a driving force to the turning base 63 and the tiltingbases 64A and 64B independently of each other.

FIG. 5 shows an example of a configuration for supplying a driving forceto the tilting bases 64A and 64B.

The drive unit 66 includes a drive motor 73 (driving force supplier) andgears 74 and 72 (driving force supplier).

The drive motor 73 is a drive source for driving the tilting bases 64Aand 64B. The type of the drive motor 73 is not limited as long as it isan appropriate motor capable of performing forward and reverse rotation.

The drive motor 73 is communicably connected to the sample holdercontrol unit 40. The operation of the drive motor 73 is controlledaccording to a control signal from the sample holder control unit 40.

The gear 74 is coaxially attached to an output shaft 73 a of the drivemotor 73.

The gear 72 is fixed coaxially to a central axis of the worm 70 at anend portion of the worm 70. The gear 72 meshes with the gear 74.

As the gears 74 and 72, a spur gear, a helical gear, or the like may beused. The gears 74 and 72 constitute a transmission mechanism fortransmitting the driving force of the drive motor 73 to the worm 70.

However, the gears 74 and 72 are examples of the transmission mechanism.The transmission mechanism may include an appropriate speed reductionmechanism. The transmission mechanism may include a transmissionmechanism other than the gear.

In the example shown in FIG. 5, the output shaft 73 a of the drive motor73 and the central axis of the worm 70 are parallel to each other.However, a gear which transmits a driving force in a state where theoutput shall 73 a of the drive motor 73 intersects the central axis ofthe worm 70 may be used for the transmission mechanism.

With such a configuration, the sample holder 6 is a biaxial tiltingstage in which the turning base 63 and the plane portions 64 b of thetilting bases 64A and 64B tilt in the y-axis direction by the turningabout the axis F and the plane portions 64 b of the tilting bases 64Aand 64B tilt in the x-axis direction by the turning about the axis S1and the axis S2.

The worm 70, the gears 74 and 72, and the drive motor 73 constitute adriving force supplier which supplies a driving force for turning thetilting bases 64A and 64B together with each other.

Here, the TEM grid 67 and the samples 7A and 7B will be described.

FIGS. 7A and 7B show a schematic front view and side view showing theholding form of the sample in the charged particle beam apparatusaccording to the first embodiment of the present invention. FIG. 8 is aschematic perspective view showing a relationship between the sample anda processing direction in the charged particle beam apparatus accordingto the first embodiment of the present invention.

As shown in FIGS. 7A and 7B, the TEM grid 67 is made of a thin plate,and a sample holding base 67 a is formed at the center. Five columns 67b 1, 67 b 2, 67 b 3, 67 b 4, and 67 b 5 are formed on the sample holdingbase 67 a.

Examples of the sample attached to the upper part of the columns 67 b 1to 67 b 5 include a minute thin sample 7A (7B) shown in FIG. 8.

The sample 7A (7B) is formed by cutting out a part of a semiconductordevice, for example. The sample 7A (7B) includes structures 31, 32, and33. The structures 31 and 33 are exposed on a cross section 7 a as anobservation surface. The sample 7A (7B) is attached to the columns 67 b1 to 67 b 5 such that the FIB, the EB, and the GIB are emitted from anupper surface 7 c side.

In the present embodiment, when the tilting base 64A (64B) is at areference position, the sample 7A (7B) is attached such that a normaldirection of the cross section 7 a (the thickness direction of thesample 7A (7B)) is substantially the y-axis direction.

In the present embodiment, the sample 7A on the column 67 b 3 isdisposed at an intersection of the axis F and the axis S1. Similarly,the sample 7B on the column 67 b 3 is disposed at an intersection of theaxis F and the axis S2.

Next, the operation of the charged particle beam apparatus 100 will bedescribed focusing on the effect of the sample holder 6.

The charged particle beam apparatus 100 can perform at least one ofprocessing, observation, and analysis (hereinafter, may be referred toas “processing or the like”) on the samples 7A and 7B according to anoperation input from the input unit 16.

The samples 7A and 7B are shaped in advance to an appropriate size andthen held on, for example, the TEM grid 67. For example, the TEM grid 67holding the sample 7A is held by the sample holding portion 64 c on thetilting base 64A of the sample holder 6 as shown in FIG. 4. At thistime, the TEM grid 67 is held by the sample holding portion 64 c suchthat a straight line T connecting the upper surface of the sample 7A issubstantially parallel to the axis F (see FIGS. 7A and B) and thestraight line T is positioned at substantially the same height as theaxis S. Similarly, the TEM grid 67 holding the sample 7B is held by thesample holding portion 64 c on the tilting base 64B of the sample holder6.

Such a disposing operation of the TEM grid 67 is performed in a statewhere the sample holder 6 is carried out of the charged particle beamapparatus 100. Thus, precise alignment can be obtained by using anappropriate jig, a measuring device, or the like. Further, such adisposing operation of the TEM grid 67 may be performed by an operatordifferent from the operator of the charged particle beam apparatus 100.

In parallel with this, preparation for operation of the charged particlebeam apparatus 100 is performed. For example, the control unit 17 sendsa control signal to the sample stage control unit 15, and the samplestage 10 initializes the position of each stage to the referenceposition for each movement.

Thereafter, the sample holder 6 holding the samples 7A and 7B isdisposed on the sample base 5 a of the sample stage 10 of the chargedparticle beam apparatus 100. When the sample holder 6 is fixed to thesample base 5 a in a positioning state, the sample chamber 9 isevacuated. However, when the charged particle beam apparatus 100includes a load lock chamber, evacuation may be completed during thepreparing for operation. In this case, the operator can install thesample holder 6 on the sample base 5 a through the load lock chamberwhile the sample chamber 9 is maintained in a vacuum state.

Thereafter, the control unit 17 controls each portion of the chargedparticle beam apparatus 100 based on an operation input from the inputunit 16 of the operator, and thereby the samples 7A and 7B areprocessed. Hereinafter, an example in which the sample 7B is processedafter the sample 7A is processed will be described.

For example, the operator causes the display unit 18 to display the SEMimage or SIM image of the sample 7A. The operator sets, for example, anirradiation region of the FIB 1 b based on an observation image such asan SEM image or an SIM image displayed on the display unit 18. Theoperator inputs a processing frame for setting an irradiation region onthe observation image displayed on the display unit 18 through the inputunit 16.

When the operator inputs an instruction to start the processing to theinput unit 16, an irradiation region and a processing start signal aretransmitted from the control unit 17 to the FIB control unit 11, and theFIB is emitted from the FIB control unit 11 onto a designatedirradiation region of the sample 7A. Accordingly, the FIB 1 b is emittedonto the irradiation region input by the operator.

In the charged particle beam apparatus 100, in order to perform SEMobservation on the sample 7A (7B) being processed by the FIB 1 b, asshown in FIG. 2, the FIB irradiation axis 1 a intersects the EBirradiation axis 2 a. The operator drives the sample stage 10 by anoperation input from the input unit 16 such that the sample 7A (7B) isaligned at a position where the FIB irradiation axis 1 a intersects theEB irradiation axis 2 a.

After the alignment, when an operation input for rotating the rotationstage 5 is performed, a control signal is sent from the control unit 17to the sample stage control unit 15. The rotation stage 5 is rotatedunder the control of the sample stage control unit 15. As a result, thesample 7A (7B) is rotated about the rotation axis C in a state where theSEM image can be observed.

Further, when an operation input for turning the tilting base 64A (64B)of the sample holder 6 about the axis F or the axis S1 (S2) isperformed, a control signal is sent from the control unit 17 to thesample holder control unit 40. The tilting base 64A (64B) of the sampleholder 6 is tilted in the y-axis direction or the x-axis direction underthe control of the sample holder control unit 40. As a result, thesample 7A (7B) is tilted in the y-axis direction or the x-axis directionin a state where the SEM image can be observed. Here, the tilting in thex-axis direction is a tilting caused by turning in a directionrepresented by arrows SR1 and SR2 in FIG. 7A. The tilting in the y-axisdirection is a tilting caused by turning in a direction represented byarrows FR1 and FR2 in FIG. 7B.

Thus, in the charged particle beam apparatus 100, after aligning thesample 7A (7B), it is easy and highly accurate to rotate the sample 7A(7B) about the rotation axis C and tilt the same in the x-axis directionor the y-axis direction in a eucentric state.

Thus, according to the charged particle beam apparatus 100, theprocessing which prevents the curtain effect can be performed easily.

For example, as shown in FIG. 8, the position of the sample 7A (7B) ismoved by the sample stage 10 and the sample holder 6, and the chargedparticle beam is emitted from the direction of an arrow B1 to processthe cross section 7 a. In this case, in the cross section 7 a, theetching rate is different between a portion where the structures 31 and33 are exposed and a portion where other semiconductors are exposed. Anunevenness is formed on the cross section 7 a. This phenomenon is knownas the so-called curtain effect.

When SEM observation is performed on the cross section 7 a on which theunevenness is formed, the observed image includes streaks caused by theunevenness. Since these streaks are formed by ion beam processing, thesestreaks are not semiconductor device structures or defects. Whenoccurring in the observed image, the streaks may be indistinguishablefrom structures of the semiconductor device or defect.

However, according to the charged particle beam apparatus 100, bytilting the tilting base 64A (64B) in the x-axis direction from thisstate, the irradiation direction of the charged particle beam can beeasily changed as shown by the arrow B2 while maintaining the eucentricstate. For example, even when the cross section 7 a is tilted in they-axis direction due to an attaching error of the TEM grid 67, therotation in the plane of the cross section 7 a can be performed by theoperator performing an operation input for finely adjusting the tiltingin the y-axis direction while observing the cross section 7 a.

Thus, the unevenness generated by the curtain effect can be reduced byrepeating a finishing processing of checking the charged particle beamfrom a plurality of directions along the cross section 7 a.

When all necessary processing, observation and analysis for sample 7Aare complete, the operator performs an operation input for driving thesample stage 10 and moves the sample holder 6 in the x-axis direction bya separation distance from the sample 7B to the sample 7A. Since in thesample holder 6, the separation distance from the sample 7B to thesample 7A is determined as a disposed pitch in the x-axis direction ofthe tilting bases 64A and 64B, such a movement operation can beautomatically controlled by the control unit 17 based on an operationinput of movement start by the operator.

When the movement of the sample holder 6 in the x-axis direction iscompleted, the sample 7B is positioned in the irradiation region of thecharged particle beam instead of the sample 7A. Thus, the operator canstart processing, observing, and analyzing the sample 7B immediatelyafter the sample holder 6 is moved. However, when the posture of thesample 7B needs to be finely adjusted due to the attaching error of thesample 7B, the operator may finely adjust the position of the sample 7Bwith respect to the irradiation region by driving the sample stage 10 orthe sample holder 6 while observing the sample 7B before starting theprocessing.

When the sample 7B is disposed in the irradiation region of the chargedparticle beam in the same manner as the sample 7A, the sample 7B isprocessed in the same manner as the sample 7A.

According to the charged particle beam apparatus 100, the tilting base64B holding the sample 7B in the sample holder 6 is driven in the samemanner as the tilting base 64A by the drive motor 73 for driving thetilting base 64A. Further, the tilting bases 64A and 64B are bothdisposed on the turning base 63. Thus, the tilting base 64B can bedriven by the drive unit 66 in the same manner as the tilting base 64A.Thus, when processing the sample 7B, the processing which prevents thecurtain effect similar to that of the sample 7A can be performed.Particularly when the shapes of the samples 7A and 7B are the same, thesample holder control unit 40 can also perform drive control duringprocessing of the sample 7B by a drive control program for processingthe sample 7A.

When all necessary processing, observation and analysis for sample 7Bare complete, the operator takes the samples 7A and 7B out of the samplestage 10 by carrying out the sample holder 6 from the sample chamber 9.Further, when it is necessary to process another sample, the aboveprocessing or the like is performed by carrying another sample holder 6holding another sample into the sample chamber 9 in the same manner asdescribed above.

Particularly when the charged particle beam apparatus 100 includes aload lock chamber, the sample chamber 9 is kept in a vacuum state duringsuch a carrying-out operation. In this case, the operator can disposethe sample holder 6 holding the samples 7A and 7B whose positions areadjusted in advance outside the apparatus on the sample stage 10 withoutopening the sample chamber 9 to the atmosphere. Further, the operatorcan replace the sample holder 6 in the sample chamber 9 with anothersample holder 6 without opening the sample chamber 9 to the atmosphere.

Thus, the operator can continue the processing on the other samples 7Aand 7B using the charged particle beam apparatus 100 by immediatelycarrying the other sample holder 6 into the sample chamber 9.

As described above, according to the charged particle beam apparatus100, a plurality of samples 7A and 7B positioned and held on the sampleholder 6 can be carried into the sample chamber 9 and carried out fromthe sample chamber 9. Thus, by using the charged particle beam apparatus100, the operator can quickly disposed and replace the sample whenprocessing a plurality of samples. In addition, the charged particlebeam apparatus can form a sample safely and efficiently even in a caseof processing a plurality of samples.

The charged particle beam apparatus 100 can process the samples 7A and7B substantially continuously only by leaving a time for moving thesamples 7A and 7B held on the sample holder 6 to the irradiation regionof the charged particle beam. Thus, the throughput in processing thesamples 7A and 7B and the operation efficiency of the charged particlebeam apparatus 100 can be improved.

Particularly when the charged particle beam apparatus 100 includes aload lock chamber, since the sample holder 6 is carried out withoutreleasing the vacuum state of the sample chamber 9, the samplereplacement time accompanying the replacement of the sample holder 6 canbe further shortened.

According to the charged particle beam apparatus 100, when a complexprocessing such as finishing which prevents the curtain effect isperformed, since a plurality of samples are disposed on the sampleholder 6 including the tilting bases 64A and 64B interlocking with eachother, a control program for the sample holder 6 in each sample can beshared.

Further, since the tilting bases 64A and 64B are interlocked with eachother in the sample holder 6, both of the tilting bases 64A and 64B aredriven by the drive motor 73, which is a single drive source. Thus, thecomponent cost of the sample holder 6 is reduced as compared with a casewhere the tilting bases 64A and 64B are driven by different drivesources. Further, the sample holder 6 can be easily made compact.

Second Embodiment

A charged particle beam apparatus according to a second embodiment ofthe present invention will be described.

FIG. 9 is a schematic front view showing an example of an internalstructure of a sample holder in the charged particle beam apparatusaccording to the second embodiment of the present invention.

As shown in FIG. 9, a charged particle beam apparatus 101 according tothe present embodiment includes a sample holder 106 instead of thesample holder 6 of the first embodiment. Further, as shown in FIG. 9,the charged particle beam apparatus 101 includes the sample holder 106instead of the sample holder 6 of the first embodiment.

Hereinafter, the description will be given centering on differences fromthe first embodiment.

As shown schematically in FIG. 9, the sample holder 106 includes atilting base 164A (first tilting base), a tilting base 164B (secondtilting base), and a drive rod 170 (driving force supplier) instead ofthe tilting bases 64A and 64B and the worm 70 in the sample holder 6.

The tilting bases 164A and 164B have the same shape. The outer shape ofthe tilting base 164A (164B) is a substantially half-moon shape whenviewed from the y-axis direction, and a plane portion 164 a is formed ata position facing the arc portion. A sample holding portion 64 c (notshown) is disposed on the plane portion 164 a, similarly to the planeportion 64 b of the tilting base 64A (64B) of the first embodiment.

The tilting bases 164A and 164B are accommodated in the hole portion 63a (not shown) side by side in the x-axis direction. Positions of thetilting bases 164A and 164B in the y-axis direction are positioned by apositioning unit (not shown) on the inner peripheral portion of the holeportion 63 a.

The tilting base 164A (164B) includes a turning support portion 164 band an engaging portion 164 c.

The turning support portion 164 b supports the tilting base 164A (164B)with respect to the turning base 63 (not shown) to be turnable about theaxis S1 (S2) similar to that of the first embodiment. The configurationof each turning support portion 164 b is not particularly limited aslong as the tilting bases 164A and 164B can be supported to be turnableabout the axis S1 and the axis S2, respectively.

For example, the turning support portion 164 b in FIG. 9 schematicallyrepresents a mechanism including a turning support shaft coaxial withthe axis S1 (S2) and a bearing provided on the turning base 63.

For example, the turning support portion 164 b may he configured by asliding engagement portion formed on the tilting base 164A (164B) andthe turning base 63 along an arc-shaped trajectory concentric with theaxis S1 (S2).

The engaging portion 164 c is connected to the drive rod 170 forconverting a driving force transmitted by the drive rod 170, to bedescribed later into a turning force about the axis S1 (S2). As theengaging portion 164 c, an appropriate protrusion, hole, groove, or thelike may be used according to the configuration of the drive rod 170.

In the example schematically shown in FIG. 9, the engaging portion 164 cis configured by a pin member protruding in the y-axis direction in anouter peripheral side region of the tilting base 164A (164B).

The drive rod 170 is a rod-shaped member extending in the x-axisdirection. The drive rod 170 is supported by a linear guide provided onthe turning base 63 (not shown) so as to be able to advance and retreatin the x-axis direction.

The drive rod 170 includes engagement portions 170 a connected to therespective engaging portions 164 c in a state of being in contact withthe respective engaging portions 164 c of the tilting bases 164A and164B in the x-axis direction.

As the engagement portion 170 a, a configuration appropriate forcontacting and engaging the engaging portion 164 c in the x-axisdirection such that the engaging portion 164 c is freely moved in adirection orthogonal to the x-axis and the y-axis may be used.

For example, when the engaging portion 164 c is a pin member as in theexample schematically shown in FIG. 9, the engagement portion 170 a maybe configured by a long hole which penetrates in the y-axis direction inthe drive rod 170 and is long in the direction orthogonal to the x-axisand the y-axis. In this case, the engaging portion 164 c formed of a pinmember is fitted to the engagement portion 170 a formed of a long holeso as to be slidable in a longitudinal direction.

For example, when the engaging portion 164 c is configured by a holeportion, the engagement portion 170 a may be configured by a protrusionsuch as a pin.

The drive unit 166 includes a drive source 173 (driving force supplier)instead of the drive motor 73 and the gears 74 and 72 of the drive unit66 of the first embodiment. The drive source 173 is communicablyconnected to the sample holder control unit 40. The drive source 173advances and retreats the drive rod 170 in the x-axis direction based ona control signal from the sample holder control unit 40.

The configuration of the drive source 173 is not particularly limited aslong as a driving force for driving the drive rod 170 can be supplied.In FIG. 9, as an example, the drive source 173 is configured by a linearmotor for driving an output shaft 173 a in the axial direction. Theoutput shaft 173 a is disposed along the x-axis direction and isconnected to the end of the drive rod 170.

However, the output shaft 173 a of the drive source 173 is not directlyconnected to the drive rod 170, but may be connected to the drive rod170 via a transmission mechanism such as a cam, a link, or a gear.

For example, the drive source 173 may be configured by a rotation motorand a transmission mechanism for converting a rotational motion into alinear motion.

According to the sample holder 106, when the output shaft 173 a of thedrive source 173 moves in the x-axis negative (positive) direction (seethe solid line (broken line) arrow in the drawing), the drive rod 170moves in the same direction. Accordingly, a driving force in the samedirection is transmitted to the tilting bases 164A and 164B via theengaging portion 164 c engaged with the engagement portion 170 a.

When the driving force in the x-axis negative (positive) direction istransmitted from the engaging portion 164 c, the tilting base 164A(164B) turns about the axis S1 (S2) in the direction of the arrow SR1(SR2). As a result, each plane portion 164 a of the tilting bases 164Aand 164B is tilted in the x-axis direction together with the sampleholding portion 64 c (not shown).

The sample holder 106 in the present embodiment is different from thesample holder 6 in the first embodiment in the drive mechanism fortilting the tilting bases 164A and 164B. However, similarly to the firstembodiment, the sample holder 106 can tilt the tilting bases 164A and164B together with each other in the x-axis direction based on thecontrol signal from the sample holder control unit 40.

Thus, according to the charged particle beam apparatus 101, the samplecan be quickly disposed and replaced, similarly to the first embodiment.In addition, the charged particle beam apparatus can form a samplesafely and efficiently even in a case of processing a plurality ofsamples.

Further, according to the present embodiment, since the driving force istransmitted to the tilting bases 164A and 164B via the drive rod 170,the configuration of the tilting bases 164A and 164B is simplifiedcompared with a case where the worm wheel is formed. Thus, according tothe sample holder 106, the manufacturing cost of the sample holder 106can be reduced, or the configuration of the sample holder 106 can bemade compact.

Third Embodiment

A charged particle beam apparatus according to a third embodiment of thepresent invention will be described.

FIG. 10 is a schematic front view showing an example of an internalstructure of a sample holder in the charged particle beam apparatusaccording to the third embodiment of the present invention.

As shown in FIG. 10, a charged particle beam apparatus 102 according tothe present embodiment includes a sample holder 206 instead of thesample holder 6 of the first embodiment. Further, as shown in FIG. 10,the charged particle beam apparatus 102 includes the sample holder 206instead of the sample holder 6 of the first embodiment.

Hereinafter, the description will be given centering on differences fromthe first embodiment.

As shown schematically in FIG. 10, the sample holder 206 includes atilting base 264A (first tilting base), a tilting base 264B (secondtilting base), and a spur gear 270 (third gear, driving force supplier)instead of the tilting bases 64A and 64B and the worm 70 in the sampleholder 6.

The tilting bases 264A and 264B have the same shape. The outer shape ofthe tilting base 264A (264B) is a substantially half-moon shape whenviewed from the y-axis direction, and a plane portion 264 a is formed ata position facing the arc portion. A sample holding portion 64 c (notshown) is disposed on the plane portion 264 a, similarly to the planeportion 64 b of the tilting base 64A (64B) of the first embodiment.

The tilting bases 264A and 264B are accommodated in the hole portion 63a (not shown) side by side in the x-axis direction. Positions of thetilting bases 264A and 264B in the y-axis direction are positioned by apositioning unit (not shown) on the inner peripheral portion of the holeportion 63 a.

The tilting base 264A (264B) includes a turning support portion 264 band a spur gear 264 c.

The turning support portion 264 b supports the tilting base 264A (264B)with respect to the turning base 63 (not shown) to be turnable about theaxis S1 (S2) similar to that of the first embodiment. The configurationof each turning support portion 264 b is not particularly limited aslong as the tilting bases 264A and 264B can be supported to be turnableabout the axis S1 and the axis S2, respectively.

For example, the turning support portion 264 b may have the sameconfiguration as the turning support portion 164 b of the secondembodiment.

For example, the turning support portion 264 b may have a configurationin which the roller 65 and the guide groove 64 e are combined as in thefirst embodiment.

The spur gear 264 c of the tilting base 264A (264B) is formed such thatthe pitch circle center is coaxial with the axis S1 (S2) on anarc-shaped outer periphery of the tilting base 264A (264B). The spurgear 264 c of the tilting base 264A constitutes a first gear having theaxis S1 which the first turning axis as the pitch circle center. Thespur gear 264 c of the tilting base 264B constitutes a second gearhaving the axis S2 which the second turning axis as the pitch circlecenter.

The spur gear 270 includes a module which meshes with each spur gear 264c. The spur gear 270 is disposed at a position where the spur gear 270meshes with each spur gear 264 c at a middle portion below the tiltingbases 264A and 264B.

A drive unit 266 is configured by deleting the gears 74 and 72 from thedrive unit 66 of the first embodiment. Further, in the drive unit 266,at least the drive motor 73 is disposed at a position coaxial with thepitch circle center of the spur gear 270 in the turning base 63.

The drive motor 73 in the present embodiment is fixed to the spur gear270 at a tip of the output shaft 73 a. The drive motor 73 in the presentembodiment rotates the spur gear 270 counterclockwise (see solid linearrow) or clockwise (see broken line arrow) shown in the figure based ona control signal from the sample holder control unit 40.

However, the output shaft 73 a of the drive motor 73 is not directlyconnected to the spur gear 270, but may be connected to the spur gear270 via a transmission mechanism including an appropriate gear train,speed reduction mechanism, or the like.

According to the sample holder 206, when the output shaft 73 a of thedrive motor 73 rotates counterclockwise shown in the figure (clockwiseshown in the figure), each spur gear 264 c turns in the direction of thearrow SR1 (SR2). Accordingly, each plane portion 264 a of the tiltingbases 264A and 264B is tilted in the x-axis direction together with thesample holding portion 64 c (not shown).

Thus, the sample holder 206 in the present embodiment is different fromthe sample holder 6 in the first embodiment in the drive mechanism fortilting the tilting bases 264A and 264B. However, similarly to the firstembodiment, the sample holder 206 can tilt the tilting bases 264A and264B together with each other in the x-axis direction based on thecontrol signal from the sample holder control unit 40.

Thus, according to the charged particle beam apparatus 102, the samplecan be quickly disposed and replaced, similarly to the first embodiment.In addition, the charged particle beam apparatus can form a samplesafely and efficiently even in a case of processing a plurality ofsamples.

Further, according to the present embodiment, since the driving force istransmitted to the tilting bases 264A and 264B by the meshing of thespur gears, the manufacturing cost of the tilting bases 264A and 264B isreduced compared with a case where the worm wheel is formed.

Fourth Embodiment

A charged particle beam apparatus according to a fourth embodiment ofthe present invention will be described.

FIG. 11 is a schematic front view showing an example of an internalstructure of a sample holder in the charged particle beam apparatusaccording to the fourth embodiment of the present invention. In FIG. 11,the z-axis direction is a direction orthogonal to the x-axis directionand the y-axis direction.

Among the configurations of the fourth embodiment, configurations otherthan those described below are the same as those in the first or secondembodiment.

A sample holder 406 includes a first tilting base 464A, a second tiltingbase 464B, and a driving force supplier 470. The first tilting base 464Aincludes a tilting base body 464, a turning support portion 468, and anengaging portion 469.

The tilting base body 464 is formed in a substantially cylinder shapethat is substantially a semicircular when viewed from the y-axisdirection. The tilting base body 464 includes a plane portion FS and anarc portion RS on an outer periphery thereof. The sample 7A is disposedon the plane portion FS via a sample holding portion and a TEM grid.

The turning support portion 468 is formed in a cylindrical pin shape,for example. The turning support portion 468 protrudes in the y-axisdirection from an end surface of the tilting base body 464 in the y-axisdirection. A central axis of the turning support portion 468 coincideswith the axis S1. The turning support portion 468 supports the tiltingbase body 464 such that the tilting base body 464 can turn about theaxis S1.

The engaging portion 469 is formed in a cylindrical pin shape, forexample. The engaging portion 469 protrudes in the y-axis direction fromthe end surface of the tilting base body 464 in the y-axis direction.The engaging portion 469 is separated from the turning support portion468 and is disposed near the arc portion RS. A separation direction ofthe turning support portion 468 and the engaging portion 469 is parallelto the plane portion FS.

The configuration of the second tilting base 464B is the same as that ofthe first tilting base 464A. The turning support portion 468 of thesecond tilting base 464B supports the tilting base body 464 such thatthe tilting base body 464 can turn about the axis S2. The sample 7B isdisposed on the plane portion FS via a sample holding portion and a TEMgrid.

The driving force supplier 470 includes a drive arm 475 and a drivesource 473.

The drive arm 475 is formed in a substantially U-shaped plate shape whenviewed from the y-axis direction. The drive arm 475 is disposed in they-axis direction of the tilting bases 464A and 464B. The drive arm 475is disposed with both tip portions directed in the z-axis direction.Engagement portions 479 are formed at both tip portions of the drive arm475. The positions of the engagement portions 479 at both tip portionsin the z-axis direction are the same. The engagement portion 479 is athrough hole penetrating the drive arm 475 in the y-axis direction, forexample. The engagement portion 479 is formed in an oval shape whenviewed from the y-axis direction. In the oval of the engagement portion479, the major axis direction is the x-axis direction, and the minoraxis direction is the z-axis direction. The engagement portion 479 isinserted with an engaging portion 469 of each of the tilting bases 464Aand 464B. At this time, the plane portions FS of the tilting bases 464Aand 464B are disposed in the same plane or at the same tilting angle.Accordingly, the samples 7A and 7B disposed on the plane portions FS ofthe tilting bases 464A and 464B have the same angle about the y-axis.

A drive source 473 is connected to a base end portion of the drive arm475. The drive source 473 moves the drive arm 475 in the z-axisdirection based on a control signal from the sample holder control unit40. The drive source 473 is, for example, a piezoelectric element. Thedrive source 473 may be a ball screw mechanism, for example.

Next, the operation of the sample holder 406 will be described.

The drive source 473 moves the drive arm 475 in the z-axis direction.The engagement portion 479 of the drive arm 475 moves the engagingportion 469 of each of the tilting bases 464A and 464B in the z-axisdirection. Accordingly, each of the tilting bases 464A and 464B turnsabout the axis S1 and the axis S2. As the tilting bases 464A and 464Bturns, the engaging portion 469 moves in the x-axis direction. Since theengagement portion 479 of the drive arm 475 is formed in an oval shape,the engaging portion 469 is allowed to move in the x-axis direction. Theangle of the samples 7A and 7B disposed on the plane portion FS aboutthe y-axis is changed by the turning of the tilting bases 464A and 464B.Accordingly, the processing and observation can be performed on thesamples 7A and 7B from various angles. When the drive source 473 isdriven in the same manner, the angles of the sample 7A and the sample 7Bare changed similarly. Therefore, the sample 7A and the sample 7B can beprocessed similarly.

The charged particle beam apparatus including the sample holder 406 canquickly dispose and replace the sample, similarly to the first or secondembodiment. In addition, the charged particle beam apparatus can form asample safely and efficiently even in a case of processing a pluralityof samples.

The sample holder 406 is attachable and detachable from the uppersurface of the sample stage 10 shown in FIG. 2. That is, the drivesource 473 supplies a driving force in the z-axis direction intersecting(orthogonal to) the upper surface of the sample stage 10. The sampleholder 406 is compact in the x-axis direction and the y-axis direction.Therefore, even when there are structures on the sample stage 10 in thex-axis direction and the y-axis direction, the sample holder 406 whichdoes not interfere with the structure can be provided.

In the fourth embodiment, the drive arm 475 is formed in a substantiallyU-shaped plate shape. In contrast, the drive arm 475 may be configuredby a link mechanism. For example, the drive arm 475 may include a basearm connected to the drive source 473 and a pair of turning armspin-coupled to both end portions of the base arm. A circular throughhole is formed at a tip of the turning arm when viewed from the y-axisdirection. The engaging portion 469 of each of the tilting bases 464Aand 464B is inserted into the through hole. Accordingly, when thetilting bases 464A and 464B are turned by the drive source 473, thepositional accuracy of the tilting bases 464A and 464B is improved.

Modification of Fourth Embodiment

A charged particle beam apparatus according to a modification of thefourth embodiment will be described.

FIG. 12 is a schematic front view showing an example of an internalstructure of a sample holder in the charged particle beam apparatusaccording to the fourth embodiment of the present invention.

In the modification with respect to the fourth embodiment, the positionof an engaging portion 469 m of the first tilting base 464A isdifferent. Among the configurations of the modification, configurationsother than those described below are the same as those in the fourthembodiment.

The engaging portion 469 m of the first tilting base 464A is separatedfrom the turning support portion 468 and is disposed near the arcportion RS. A separation direction of the turning support portion 468and the engaging portion 469 m is a direction intersecting (orthogonalto) the plane portion FS. The position of the engaging portion 469 ofthe second tilting base 464B is the same as in the fourth embodiment.

The engagement portion 479 of the drive arm 475 is inserted with theengaging portion 469 m of each of the tilting bases 464A and 464B.Accordingly, the plane portion FS of the first tilting base 464A and theplane portion FS of the second tilting base 464B are disposed atdifferent tilting angles an orthogonal state). At this time, the samples7A and 7B disposed on the plane portions FS of the tilting bases 464Aand 464B are greatly different in angle about the y-axis.

In a sample holder 406 m of the modification, the sample 7A and thesample 7B can be processed from greatly different angles.

In the modification, one engaging portion 469 m is formed near the arcportion RS. In contrast, a plurality of engaging portions 469 m may beformed along the arc portion RS. In this case, when a different engagingportion 469 m is inserted into the engagement portion 479, the tiltingangle of the plane portion FS is changed. Accordingly, the angle of thesample 7A about the y-axis can be changed.

Fifth Embodiment

A charged particle beam apparatus according to a fifth embodiment of thepresent invention will be described.

FIG. 13 is a schematic front view showing an example of an internalstructure of a sample holder in the charged particle beam apparatusaccording to the fifth embodiment of the present invention.

Among the configurations of the fifth embodiment, configurations otherthan those described below are the same as those in the first or thirdembodiment.

A sample holder 506 includes a first tilting base 564A, a second tiltingbase 564B, and a driving force supplier 570. The first tilting base 564Aincludes a tilting base body 564, a turning support portion 568, and anarc gear (first gear) 569.

The tilting base body 564 is formed in a substantially cylinder shapethat is substantially a semicircular when viewed from the y-axisdirection. The tilting base body 564 includes a plane portion FS and anarc portion RS on an outer periphery thereof. The sample 7A is disposedon the plane portion FS via a sample holding portion and a TEM grid.

The turning support portion 568 is formed in a cylindrical pin shape,for example. The turning support portion 568 protrudes in the y-axisdirection from an end surface of the tilting base body 564 in the y-axisdirection. A central axis of the turning support portion 568 coincideswith the axis The turning support portion 568 supports the tilting basebody 564 such that the tilting base body 564 can turn about the axis S1.

The arc gear 569 is a part of the outer periphery of the gear. The arcgear 569 is formed on the arc portion RS of the tilting base body 564.The pitch circle center of the arc gear 569 coincides with the axis S1.

The configuration of the second tilting base 564B is the same as that ofthe first tilting base 564A. The turning support portion 568 of thesecond tilting base 564B supports the tilting base body 564 such thatthe tilting base body 564 can turn about the axis S2. The pitch circlecenter of the arc gear (second gear) 569 coincides with the axis S2. Thesample 7B is disposed on the plane portion FS via a sample holdingportion and a TEM grid.

The driving force supplier 570 includes a pinion gear (third gear) 579,a rack gear 575, and a drive source 573.

The pinion gear 579 is a spur gear. The pinion gear 579 is disposed at amiddle portion between the tilting bases 564A and 564B in the x-axisdirection. The pinion gear 579 meshes with the arc gears 569 of thetilting bases 564A and 564B. That is, one pinion gear 579 meshes withthe arc gears 569 of the tilting bases 564A and 564B.

The rack gear 575 is disposed in parallel to the x-axis direction. Therack gear 575 is disposed on a side opposite to the tilting bases 564Aand 564B with the pinion gear 579 interposed therebetween. The rack gear575 meshes with the pinion gear 579. At this time, the plane portions FSof the tilting bases 564A and 564B are disposed in parallel or in thesame plane. The samples 7A and 7B disposed on the plane portions FS ofthe tilting bases 564A and 564B have the same angle about the y-axis.

The drive source 573 is connected to the rack gear 575. The drive source573 moves the rack gear 575 in the x-axis direction based on a controlsignal from the sample holder control unit 40. The drive source 573 is aball screw mechanism, for example.

The operation of the sample holder 506 will be described.

The drive source 573 moves the rack gear 575 in the x-axis direction.The rack gear 575 rotates the pinion gear 579. The pinion gear 579 turnsthe tilting bases 564A and 564B in the same manner via the arc gear 569.The angle of the samples 7A and 7B disposed on the plane portion FSabout the y-axis is changed by the turning of the tilting bases 564A and564B. Accordingly, the processing and observation can be performed onthe samples 7A and 7B from various angles. When the drive source 573 isdriven in the same manner, the angles of the sample 7A and the sample 7Bare changed similarly. Therefore, the sample 7A and the sample 7B can beprocessed similarly.

The charged particle beam apparatus including the sample holder 506 canquickly dispose and replace the sample, similarly to the first or thirdembodiment. In addition, the charged particle beam apparatus can form asample safely and efficiently even in a case of processing a pluralityof samples.

Modification of Fifth Embodiment

A charged particle beam apparatus according to a modification of thefifth embodiment will be described.

FIG. 14 is a schematic front view showing an example of an internalstructure of a sample holder in the charged particle beam apparatusaccording to the fifth embodiment of the present invention.

In the modification with respect to the fifth embodiment, a separatepinion gear 579 m meshes with the arc gear 569 of each of the tiltingbases 564A and 564B. Among the configurations of the modification,configurations other than those described below are the same as those inthe fifth embodiment.

The pinion gear 579 m is disposed below the first tilting base 564A. Thepinion gear 579 m meshes with the arc gear 569 of the first tilting base564A. The same applies to the second tilting base 564B. That is,respective pinion gears 579 m mesh with the arc gears 569 of respectivethe tilting bases 564A and 564B. The pinion gears 579 m have the samenumber of teeth.

The rack gear 575 meshes with each pinion gear 579 m. At this time, theplane portions ES of the tilting bases 564A and 564B are disposed inparallel or in the same plane. The samples 7A and 7B disposed on theplane portions ES of the tilting bases 564A and 564B have the same angleabout the y-axis.

The charged particle beam apparatus including a sample holder 506 maccording to the modification can quickly dispose and replace thesample, similarly to the first or third embodiment. In addition, thecharged particle beam apparatus can form a sample safely and efficientlyeven in a case of processing a plurality of samples.

In the modification, the pinion gears 579 m have the same number ofteeth. In contrast, the number of teeth of the pinion gears 579 m may bedifferent. In this case, when the rack gear 575 is moved in the x-axisdirection, the tilting bases 564A and 564B are turned at differentangles. Accordingly, the plane portion FS of the first tilting base 564Aand the plane portion FS of the second tilting base 564B are disposed atdifferent tilting angles. At this time, the samples 7A and 7B disposedon the plane portions FS of the tilting bases 564A and 564B aredifferent in angle about the y-axis. Therefore, the sample 7A and thesample 7B can be processed from different angles.

In the description of the above embodiments, an example is described inwhich the FIB lens barrel 1 is disposed in the vertical direction, andthe EB lens barrel 2 and the GIB lens barrel 3 are disposed to be tiltedwith respect to the vertical axis. However, the positional relationshipbetween the FIB lens barrel 1 and the EB lens barrel 2 or the FIB lensbarrel 1 and the GIB lens barrel 3 may be interchanged.

In the description of the above embodiments, an example is described inwhich the charged particle beam which can be emitted by the chargedparticle beam apparatus is three types of FIB, EB, and GIB. However, thetype of charged particle beam and the number of irradiations are notlimited thereto. The type and number of charged particle beam are notparticularly limited as long as there are one or more.

In the description of the above embodiments, an example is described inwhich the samples 7A and 7B are held on the TEM grid 67. However, themethod for attaching the sample on the tilting base 64 is not limited tothe TEM grid 67.

In the description of the above embodiments, an example is described inwhich the sample holder is provided with a tilting stage for tilting thefirst tilting base and the second tilting base which are tilted in thex-axis direction in the y-axis direction orthogonal the x-axis. However,depending on the application or the configuration of the sample stage10, the sample holder may not be provided with a tilting stage tiltingin the y-axis direction.

The first tilting base and the second tilting base in the sample holdermay be movably supported by a moving stage other than the tilting stage.Examples of the moving stage other than the tilting stage include arotation stage and a translation stage.

In the description of the above embodiments, an example is described inwhich the plane portions of the first tilting base and the secondtilting base are tilted in parallel to each other. However, the firsttilting base and the second tilting base may be tilted in oppositedirections by being turned in opposite directions about the respectiveturning axes. For example, in the first embodiment, when a twistdirection of the teeth of the worm wheel 64 a of the tilting base 64Aand a twist direction of the teeth of the worm wheel 64 a of the tiltingbase 64B are opposite, the tilting directions of the tilting bases 64Aand 64B are also opposite.

In the description of the above embodiments, an example is described inwhich the first tilting base and the second tilting base are disposed ona straight line extending in a direction orthogonal to the first turningaxis and the second turning axis. However, the first tilting base andthe second tilting base may be disposed at positions separated from eachother in the y-axis direction.

In the description of the above embodiments, an example is described inwhich the first tilting base and the second tilting base are interlockedwith each other so as to be tilted at the same tilting angle. However,the tilting angles may be different as long as the first tilting baseand the second tilting base can be interlocked with each other. In thiscase, a tilting angle range, a tilting speed, or the like of the firsttilting base and the second tilting base can be made different from eachother.

In the first embodiment and the third embodiment, an example isdescribed in which the first gear and the second gear are formed on theouter peripheral portions of the first tilting base and the secondtilting base, respectively. However, when the first gear and the secondgear are disposed coaxially with the first turning axis and the secondturning axis, respectively, the first gear and the second gear may bedisposed on lateral sides of the first tilting base and the secondtilting base. In this case, pitch circle diameters of the first gear andthe second gear may be set regardless of outer diameters of the firsttilting base and the second tilting base.

Further, the first gear and the second gear may be connected to the bodyportions of the first tilting base and the second tilting base via aclutch or the like for releasing the transmission of the driving force.In this case, the rotation of one of the first tilting base and thesecond tilting base may be selectively stopped by a clutch or the like.For example, of the first tilting base and the second tilting base, thetilting base which is not processed or the like may be released from thetransmission of the driving force during the processing or the like.

As in such a modification, the first tilting base and the second tiltingbase may be driven by a single drive source so as to be interlocked.That is, the first tilting base and the second tilting base may notalways be tilted together with each other.

In the description of the above embodiments, an example is described inwhich the sample holder includes the first tilting base and the secondtilting base. However, for the tilting base provided in the sampleholder, there may be three or more tilting bases tilted by the samedrive source.

In the above embodiments, when a broad beam having a large beam diametercovering the sample 7A and the sample 7B disposed on the first tiltingbase and the second tilting base is emitted from the GIB lens barrel 3,since two samples can be processed at the same incident angle at thesame time, the sample can be formed efficiently.

Preferred embodiments of the present invention have been describedabove, but the present invention is not limited to these embodiments.Additions, omissions, substitutions, and other modifications can be madewithout departing from the scope of the present invention.

In addition, the present invention is not limited by the abovedescription, and is limited only by the appended claims.

This application is based on Japanese Patent Application No. 2017-060903filed with the Japan Patent Office on Mar. 27, 2017, and Japanese PatentApplication No. 2018-055231 filed with the Japan Patent Office on Mar.22, 2018, and the entire contents of Japanese Patent Application No.2017-060903 and Japanese Patent Application No. 2018-055231 areincorporated herein by reference.

1. A charged particle beam apparatus, comprising: a charged particle beam lens barrel that irradiates a sample with a charged particle beam; a first tilting base that includes a first sample holding portion capable of holding the sample, and holds the first sample holding portion to be turnable about a first turning axis; a second tilting base that includes a second sample holding portion capable of holding the sample, and holds the second sample holding portion to be turnable about a second turning axis parallel to the first turning axis; and a driving force supplier configured to supply the first tilting base and the second tilting base with a driving force for turning the first tilting base in association with the second tilting base.
 2. The charged particle beam apparatus according to claim 1, wherein the first tilting base and the second tilting base are disposed in a direction intersecting the first turning axis and the second turning axis.
 3. The charged particle beam apparatus according to claim 1, further comprising: a sample stage that includes a rotation stage being rotatable about a rotation axis extending in a direction orthogonal to the first turning axis and the second turning axis, wherein the first tilting base and the second tilting base are provided on a detachable sample holder on an upper surface of the sample stage.
 4. The charged particle beam apparatus according to claim 1, further comprising a tilting stage that turns the first tilting base and the second tilting base about a third turning axis orthogonal to the first turning axis and the second turning axis.
 5. The charged particle beam apparatus according to claim 1, wherein the first tilting base includes a first gear having the first turning axis as a pitch circle center, the second tilting base includes a second gear having the second turning axis as a pitch circle center, and the driving force supplier includes a third gear meshing with the first gear and the second gear.
 6. The charged particle beam apparatus according to claim 5, wherein the first gear is a first worm wheel; the second gear is a second worm wheel; and the third gear is a worm meshing with the first worm wheel and the second worm wheel.
 7. The charged particle beam apparatus according to claim 1, wherein the driving force supplier includes a drive rod that transmits the driving force to the first tilting base and the second tilting base.
 8. The charged particle beam apparatus according to claim 3, wherein the driving supplier supplies the driving force in a direction intersecting the upper surface of the sample stage. 